The long term objective of these studies is to establish the role played by thiol-disulfide reactions in dormancy. Emphasis has been placed initially upon identifying systems in which changes in the glutathione thiol-disulfide state accompany changes in dormancy. This led to the finding that many gram positive bacteria lack GSH and that in a variety of microorganisms GSH is not the only low molecular weight thiol. A general method of analysis for thiols and disulfides is currently being developed to allow an in depth study of these systems in order to establish the nature and function of the thiols present.